Method of producing elastic thread



Nov. 5, 1940.

METHOD OF PRODUCING ELASTIC THREAD Filed Aug. 1939 5 Sheets-Sheet i/nventor Pit ili DE E lqy,

P.. E. F. CL-AY 2,220,213 4 Nov. 5, 1940. I P. E. F. CLAY 2,220,2l3

METHOD OF PRODUCING ELASTIC THREAD Filed Aug. 1, 1959 5 Sheets-Sheet 2/nvenzfor Phl'pl. E Ola/ y,

Nov. 5, 1940. P. F. CLAY 2 2 METHOD OF PRODUCING ELASTIC THREAD FiledAug. l, 1939 5 Sheets-Sheet o 11 Pk ili a 676159,

Nov. 5, 1940.

P. E. F. CLAY METHOD OF PRODUCING ELASTIC THREAD Filed Aug. '1939 5Sheets-Sheefc 4 /nventor PI ili J lu'. lt' L'la Nov. 5, 1940. P. E. F.CLAY 2,220,213

METHOD OF PRODUCING ELASTIC THREAD Filed'Aug. l, 1939 5 Sheets-sheet 5Inventar- Philp Io'. l ciag,

Patented Nov. 5, 1940 UNITED STATES OFFECE Philip Ernest Frank Clay,Radclilfe-on-Trent, England Application August 1, 1939, Serial No.287347 In Great Britain August 12, 1938 9 Claims. (CI. 57-163) Thisinvention comprises improvements in or relating to elastic thread(including the production thereof) and fabrics embodying such thread. By"elastic thread" is meant a filament or strand of rubber, either coveredor uncovered.

In order to take up the strain or tension on elastic thread, and inorder to prevent undesired elongation thereof, while being wound onto lOa bobbin or the like and/or while being fed to a working position, suchfor example as a textile machine, it has been proposed to associate withsaid elastic thread a relatively inelastic carrier thread (i. e. athread which prevents the l5 elastic thread from stretching) such as awool thread, which carrier thread is rendered inoperative after thecomposite thread has been incorporated in fabric (e. g. if the carrierthread is of wool, it is dissolved out). The provision of such carrierthread, however, isnot in itself sufficient to eliminate certainundesirable or detrimental effects frequently produced in fabricsembodying elastic thread, particularly in woven fabrics in which all thewefts, ,or all the warps', or both, are constituted by elastic threadThus, smooth-faced fabrics such as satin abrics often' have a definitetendency to become wrinkled, when the wool carrier thread is dissolved,instead of being perfectly fiat. 30 Hitherto the elastic thread has beenslightly 4 extended when combined with the carrier thread (for examplehas been extended to a small degree by the act of combinationh Thisextension or elongation persists until, after the composite thread hasbeen incorporated in fabric, the 'carrier thread is dissolved out. Uponthe removal of the carrier thread, the associated elastic thread is freeto contract. such contraction tends to be accompanied by puckering ofthe fabric, itself undesirable. Moreover, since the degree of rmnesswith which the elastic thread is gripped in the fabric may vary atdiferent points the elastic thread may contract unevenly throughout thefabric, and therefore even if the mere fact that the elastic contractsslightly does not give the abric an uneven surface the irregularcontraction will do so. Alternatively, or in addition, an uneven surfacemay result from a variation in the extent to which 50 the elastic threadis stretched or extended along the length thereof, which variation maybe caused by a variation in the resistance ofiered to the traverse orfeed of the thread to the cvering position in a machine whereby a cattonor other wrapping or covering thread is wrapped spirally around it,and/or by virtue of twist imparted to the elastic thread during thecovering operation.

It will therefore be appreciated that the poor results hitherto obtainedwith the known com- 5 posite threads can be attributed to extension orstretching of the elasic thread, and the present invention seeks toimprove these results by the avoidance of this extension or stretch.

As viewed from one aspect,the present invention provides a compositethread, comprising elastic thread and a relatively inelastic carrierthread and characterised in that said elastic thread is in a fullyrelaxed condition. By the expression fully relaxed condition" it is tobe understood that the elastic thread is in such condition that it willnot of its own volition relax or contract. As viewed from another aspectthe invention provides a composite thread, comprising elastic thread anda relatively inelastic carrier thread and characterised in thatthe-elastic thread is free from variations in the degree i to which itis extended or stretched along its length. r i

It willbe appreciated that either the elastic thread or the carrierthread, or each of them, may consist of a single strand or of aplurality of strands. e

The two constituent threads (i.'e-. the elastic u thread and the carrierthread) may be coms'o i points, or they may be twisted or doubled together, and any of thesethree modes may be combined. According to asubsidiary feature of this invention the elastic thread is wrappedelastic thread, i. e. a rubber filament or filaments suitably 'wrapped,and the carrier thread is external to said wrapping. When thisconstruction is adopted, the two constituent threads (viz: the wrappedelastic thread and the carrier thread) may be combined by any of themodes' hereinbefore referred to, but prior to such combination it ispreferred that the wrapped elastic thread shall be boiled.

The invention also provides a method of producing a composite threadcomprising elastic thread and a relatively inelastic carried thread,which includes the step of combining with the carrier thread an equallength of completely re- 4 laxed elastic thread. Another feature of theinvention resides in a method of producing a composite thread comprisingelastic thread and a relatively inelastic carrier thread, wherein therubber thread is wrapped with a covering thread while under little or notension or stretch, is then subjected to heat treatment, and the wrappedthread is finally combined with the carrier thread.

In order that the invention may be better understood, reference will nowbe made to the accompanying d'awings, in which:

Figure 1 is a sectional elevation of a portion of the apparatus employedin the exercise of this invention.

Figure 2 is a further sectional elevation thereof.

Figure 3 is a rear elevation thereof.

Figure 4 is an elevation of a further portion of apparatus, while Figure5 is an elevation of certain wrapping apparatus ,employed in one methodaccording to the invention.

Referring now particularly to Figure 1-, in one method of combining anelastic thread with a relatively inelastic carrier thread so that thetwo can be simultaneously worked or utilized as a single compositethread, a rubber thread I 0 is taken from a loose supply (e. g. a loosecoil, pile or bundle) ll` thereof ofiering no resistance to withdrawal,and by means of a suitable machine illustrated in Fig. 1 is wound in acompletely relaxed condition with an inelastic carrier thread l2 upon abobbin or like receiving member |3 so that the component threads I 0, I2 lie side by side on the bobbin and can be simultaneously withdrawntherefrom as a composite thread; it being understood that when sowithdrawn the carrier thread |2 takes the strain from the fully relaxedrubber thread n. The composite thread so withdrawn may be combined inany desired manner, for example .by being doubled in a doubling machineof any known construction.

Figures 1 and 3 show the relevant parts of the appara'tus. Thisapparatus does not need detailed description, but it may be mentionedthat in their passage to thebobbin |3 the two constituent threads passthrough a guide ll which is suitably traversed to and fro. The bobbin !3is preferably driven by a drum 5 on a shalt IS, which drum is in surfacecontact with the bobbin so that the linear speed of 'take-up isconstant.

One machine may be employed to wind a plurality'of bobbins such as I3,and the same machine may simultaneously be employed to unwind theelastic thread o from a bobbin into the loose pile ll. This isillustrated in Figure 2. In this figure the bobbin containing theinitial supply ot elastic thread is indicated in IE.` From this bobbinthe said thread o is withdrawn through the nip between a. roller l'l anda driving drum s (which drum is advantageously fixed to the aforesaidshaft IS). Thence it descends to the floor or other support and formsthe loose pile or coil ll. While said coil or pile is fed as indicatedin Figure 2, elastic may simultaneously be abstracted as indicated inFigure 1. V

The combined rubber and carrier threads may be covered by spirallywinding therearound cotton or the like, the covering thread 'or threadsbeing carried from a supply to a covering position in any convenientmanner.

According to one method (Figure 4) of applying a surrounding covering orwrapping to the combined rubber and relatively inelastic carrierthreads, said two threads (rubber and carrier) are withdrawn from thebobbin !3 upon which same are wound side by side and are passed, at

a first wrapping station A, through a vertically disposed tube 20 or thelike about the axis of which the supply or supplies 2I of covering orwrapping thread 22 is/are adapted to rotate;

Advantageously rotation is imparted to the tube 5 20 as well as to thesupply or supplies 2| of covering thread, and the covering thread 22 iswrapped spirally about the combined rubber and carrier thread at aposition immediately beneath a fixed eye or guide 23, the coveredcomposite thread being drawn upwardly by suitable means through said eye23. Preferably the covering is fed or guided to the covering pointwithin a restricted space between the upper end of the aforesaidvertical tube 20 and the underside of a plate or member furnished withthe aforesaid eye 23, and the simuitaneous rotation of the coveringthread supply or supplies 2l and the tube 20 results inthe coveringthread 22 being applied with- 20 out imparting twist to the combinedrubber and carrier thread constituting the core. Any suitable means maybe provided for preventing or restraining ballooning of the coveringthread extending to the covering position. For example, the guidingaperture through which the core with covering thread is drawn andadjacent to which the covering is efiected, may be provided in the topof a hollow member of substantially bell shape suitably supported andextending down over the aforesaid vertically disposed tube and supplybobbins. Alternatively, one or more suitably located arms or flngers maybe provided for preventing ballooning. p

A plurality'. of covering Operations may be :5 simultaneously effected,in which case a plurality of rotary bobbins carrying the covering threadmay be spaced side by side with their axes parallel and simultaneouslyrotated by means such as` a frictional driving band. Also if desired aplurality of covering threads may be applied to the same core atdifferent positions in its length, in which case one or more threadsis/are wrapped in one direction and one or more other threads in anopposite direction.

This is illustrated in Figure 4, in which figure two wrapping Stationsor positions A and B are shown. 'The mechanism at the position A hasalready been described, and that at the upper wrapping position B issimilar to it in all material respects. Desirably, however. the twowrapping devices are rotated in opposite directions and the top one mayrotate more slowly than the bottom one, for example at three-quartersthe speed thereof. This insures that .the pitch of the outer wrappingapplied at the station B is greater than the pitch of the inner wrappingapplied at the station A.

Upon leaving the wrapping device at station B the wrapped compositethread is wound under no tension on to a suitable bobbin or the like.

Instead of applying the covering thread or threads to the combinedrubber and carrier thread as above. the rubber may be covered or wrappedprevious to combining same with the inelastic carrier thread, in whichcase the covered rubber thread is so produced or treated`as to removecrinkles or kinks therefrom and fix same in a fully relaxed condition,i. e. in a condition beyond which same will not of its own volitionrelax further, irrespective of any tension that may have been applied tothe rubber during the wrapping thereof. For` example, two coveringthreads may be spirally wrapped about the rubber thread in succession,in opposite directions, 75

the second wrapping being if desired more closely applied than the firstand functioning to remove or assist in removing kinks or wrinkles formedin the rubber between the turns of the first wrappiig and nullify orsubstantially nullify the twist produced in said rubber at said firstwrapping operation; the thread so covered being heat-treated such as byboiling or by applying steam heat for a sufiicient period, say forexample half an hour, so as to fix same against further relaxation ofits own volition irrespective of any stretch or elongation that may havebeen applied to the rubber during the covering operation.

This method of covering the thread is illustrated in Figure 5. Theelastic thread is taken from a supply bobbin IS and is passed through awrapping device at a wrapping station A. It

- will be noted that this device may incorporate a yer, but as saiddevice is otherwise substantially identical with the devices illustratedin Figure 4, no further description thereof is necessary. If a secondwrapping is desired, the wrapped thread is passed through a secondwrapping device at an upper station B; thence it passes .to winding-upmechanism which in the Construction illustrated comprises a hank winder.The hanks of wrapped elastic thread are then boiled, steam heated orotherwise heat treated, fully to relax them.

The fully relaxed covered elastic is then combined with a wool or likeinelastic carrier thread whilst maintaining the elastic thread in thefully relaxed condition. This may be efi'ected by first forming a loosepile of the elastic thread in the fully relaxed condition as alreadydescribed With reference to Figure 2. The elastic thread is thenwithdrawn from this loose pile in a fully relaxed condition, and woundside by side on to a carrier with the inelastic carrier thread which is.withdrawn simultaneously from a source of supply, the elastic threadbeing maintained in a fully relaxed condition as previously describedwith reference to Figure 1. The two threads may then be combined bywithdrawing them as one composite thread and doubling them together in adoubling machine of any known construction.

If desired, instead of doubling the two threads together, the carrierthread may, as before stated, be combined with rubber thread to form acomposite thread by integrally connecting or positively adhering onethread to the other. This composite thread may be produced by connectingthe relatively inelastic thread to the rubber at intervals in itslength, or said inelastic thread may be adhered to the rubber along itsentire length. For example, the adherence of the two threads may beefiected by partially fusing the rubber or rendering same tacky so thatthe wool or like inelastic thread becomes adhered thereto, and this canbe accomplished by the action of a suitable rubber solvent or otherwise.

The positively adhered or integrally connected rubber and carrierthreads may have one or more spiral wrappings of cotton or othercovering material applied'thereto.

This invention also includes fabric incorporating elastic threadaccording to this invention, the carrier thread having been renderedinoperative. The invention further includes a method of producing fabricwherein there is fed, to a fabricating postion at which theyareincorporated as one in the fabric under manufacture, a completelyrelaxed elastic thread and an equal length of inelastic carrier thread,and wherein subsequent to the said incorporation the carrier thread isrendered inoperative to restrain extension of the elastic thread. Thecarried thread is preferably of a nature difierent from any othertextile thread incorporated in the fabric (i. e. the covering threadand/or textile thread forming part of the structure of the fabric) suchthat it may be dissolved out of the fabric without injuring said othertextile thread, but the carrier thread may be rendered inoperative bybreaking it at appropriate intervals.

I claim:

1. A method of producing composite thread, comprising elastic thread anda relatively inelastic thread, which comprises wrapping the elasticthread in a relaxed condition, subjecting the wrapped thread to heattreatment to relax it fully, and combining said relaxed wrapped elasticthread in an untensioned condition with an equal length of carrierthread.

2. A method of producing a composite thread comprising an elastic threadand a relatively inelasticcarrier thread, which consists in forming aloose pile of said elastic thread in a relaxed condition, withdrawingsaid thread from said pile, simultaneously withdrawing the carrierthread from a source of supply, winding both of said threads side byside on to a carrier, and in doubling the elastic thread with theinelastic carrier thread, the elastic thread being maintained in arelaxed condition throughout all the Operations.

3. A method of producing a composite thread comprising elastic threadand a relatively inelastic carrier thread, which consists in forming aloose pile of said elastic thread in a relaxed condition, withdrawingsaid thread from said pile under substantially no tension,simultaneously withdrawing the carrier thread from a source of supply,winding said carrier thread and said elastic thread side by side on to acarrier, doubling the elastic thread with the inelastic carrier thread,and in covering the thus formed doubled thread with a covering material,the elastic thread being maintained in a relaxed condition throughoutall the Operations.

4. A method of producing a composite thread comprising an elastic threadand a relatively inelastic carrier thread, which consists in withdrawingthe elastic thread from a source of supply, covering said thread With acovering material, heat treating said covered thread to relax thecovered thread fully, forming a loose pile of said fully relaxed coveredthread, withdrawing said thread from said loose pile in a fully relaxedcondition, simultaneously withdrawing the inelastic carrier thread froma source of supply, winding said threads side by side onto acarrierwhilst maintaining said elastic thread in a fully relaxed condition, andin doubling said elastic thread together with the inelastic carrierthread whilst maintaining the elastic thread in a fully relaxedcondition.

5. In the manufacture of fabric` having an` elastic thread, a method ofsupplying the elastic thread in a completely relaxed condition to afabricating position, which method consists in withdrawing the rubberthread from a loose supply thereof in a completely relaxed condition;si-

multaneously withdrawing an inelastic carrier thread from a supply,wi-nding the elastic thread in a completely relaxed conditionsimultaneously with the inelastic carrier thread upon 'a receiv- 5 6. Inthe manufacture of fabric having an elastic thread, a method ofsupplying the elastic thread in a completely relaxed condition to afabricating position, which method consists in withdrawing the rubberthread from a loose supply thereof in a completely relaxed condition,si-

multaneously' withdrawing an inelastic thread from a source of supply,doubling said .elastic thread `with said inelastic thread, working saidinelastic thread and elastic thread as a single composite thread, thesaid inelastic thread restraining extension ofsaid elastic thread, andin subsequentl rendering said inelastic thread inoperative to restrainextension of said elastic thread.

7. A method of producing a composite thread comprising' an elasticthread and a relatively inelastic carrier thread, in which the elasticthread is substantially fully relaxed and within a given length of thecomposite thread has the same length as the aecompanying carrier thread,which comprises providing a loose supply oi' the elastic thread whereinsaid thread lies in a iully of carrier thread upon a carrier by rotationof the latter.

8. A method oi' making a composite thread comprising an elastic threadand an inelastic carrier thread and wherein the elastic thread is in asubstantially relaxed condition, which method comprises establishing asupply of elastic thread consisting of a loose pile of such thread in astate of complete relaxation, and a supply of carrier thread,withdrawing the two threads simultaneously from their respectiveSupplies while maintaining the elastic thread substantially in its fullyrelaxed condition, winding them side by side into a rotating holder,-and subsequently withdrawing the two threads as one from said holderand combining them.

9. A method of making a composite thread comprising an elastic threadand an inelastc carrier thread and wherein the elastic thread is in asubstantially relaxed condition, which method comprises establishing asupply of elastic thread consisting of a loose pile of such thread in astate of complete relaxation, and a supply of carrier thread,withdrawing the two threads simultaneously from their respectiveSupplies while maintaining the elastic thread substantially in its iullyrelaxed condition, winding them side by side into a. rotating holder,and subsequently withdrawing the two threads asone rrom said 'holder andsecuring them to each other along their length. 7

- PHILIP ERNEST FRANK CLAY. V

